That left Adam Forshaw to step up and score the winning spot-kick and send the Bees to Wembley, where they will face West Country rivals Yeovil Town a week on Sunday for a place in the Championship.

Certainly nobody leaves a Brentford game early these days - Kevin O'Connor's injury-time penalty had secured a 1-1 draw in the first leg at the County Ground just 48 hours earlier.

That meant the momentum was with Brentford and they were gifted a 24th-minute lead when Harry Forrester whipped in a corner and Adam Rooney diverted the ball past his own keeper.

Brentford sensed they could kill Swindon off in the first half and recalled striker Trotta thumped a shot against a post.

They got their second in the 40th minute when Clayton Donaldson collected the ball on the edge of the Swindon area and slotted a low drive past Wes Foderingham and into the corner of the net.

But Swindon were thrown a lifeline before the interval when Tom Adeyemi and Toumani Diagouraga got themselves into an almighty muddle on the halfway line. Town broke clear through Gary Roberts, and when his shot was blocked, Rooney was on hand to tuck in the rebound.

However, Roberts suffered brain freeze moments after the restart when his sloppy pass on the halfway line sent Donaldson racing towards goal before coolly dinking the ball over Foderingham to restore Brentford's two-goal advantage.

Yet Swindon refused to go away quietly and in the 57th minute, when Brentford failed to clear Raffaele De Vita's corner, Joe Devera swept the loose ball high into the net.

Bees substitute Sam Saunders could have wrapped up victory but his curler clipped the crossbar, and instead, five minutes into stoppage time, Flint nodded in Roberts' corner to stun the hosts again and take the tie into extra time.

Swindon Town's Aden Flint (right) celebrates after scoring to take the match into extra time. Credit: John Walton/PA Wire

Swindon were reduced to 10 men when Nathan Byrne was shown a second yellow for deliberate handball and Foderingham twice saved from Donaldson to take the tie to penalties.

But the Bees kept their nerve in the shoot-out and Forshaw's effort sparked a pitch invasion and wild scenes of celebration, relief and disbelief.

Brentford's Harry Forrester is mobbed by home fans on the pitch after the final whistle. Credit: Andrew Matthews/EMPICS Sport